Messages

6581

General Mach Discussion / Re: Lost Steps

« on: July 06, 2011, 12:57:19 AM »

I understand your frustration S but your machine should follow the instructions it is given by Mach and be in exactly the position the Mach DRO says it is. When there is a discrepancy, as in your case, then for some reason steps have been lost (or gained). Gained steps are often caused by electrical noise pickup but steps gained in one direction can appear as steps lost when the axis travels in the opposite direction. Lost steps are often caused by insufficient drive torque or mechanical problems.

As your machine is belt driven, could the belt be slipping or jumping a tooth on the pulley ?.
Have you checked the tightness of all the grub screws associated with the drive train to the Z Axis ?.

Tweakie.

6582

General Mach Discussion / Re: Rotary + CV + G00 = Clunk

« on: July 05, 2011, 08:37:20 AM »

I think your problem relates to the exceptionally high speed you have set for the rotary axis and because it's movement is on the same GCode line as the X and Z you are getting a 'Blended Feedrate' which is higher than either your X or Z can individually tolerate - thus the 'clunk' and missed steps.

Tweakie.

6583

General Mach Discussion / Re: Motherboards-microATX that works

« on: July 05, 2011, 01:48:42 AM »

Glad you got it sorted John.

Thinking about your post, maybe it would be a good idea to have a post compiling all the motherboard types that do work well with the latest versions of Mach. 

Tweakie.

6584

General Mach Discussion / Re: parrallel pin out and comms with driver board

« on: July 04, 2011, 12:38:16 PM »

Harry,

On the main Mach screen open Config / Ports and Pins. There are tabs for Input Signals and Output Signals - these will show you the available pin numbers and their allocations which you can set as required.

Tweakie.

6585

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: July 04, 2011, 04:56:06 AM »

Glad everything is coming together for you Mikee.

I am looking forward to seeing some pictures of the stuff you make (If the river keeps rising a boat could be good  )

Tweakie.

6586

General Mach Discussion / Re: Lost Steps

« on: July 04, 2011, 04:48:51 AM »

Thanks. I just hate having to ask tons of questions without offering some form of suggestion.

So, Your Z is physically short on dimension when coming back to zero and Mach is OK. I would guess at two possibilities;

1) Missed steps and the cause being that the motor does not have enough torque to raise the axis under all conditions. This could be stiffness in the axis (which you have already eliminated) or the motor drive electronics (drop in voltage from the PSU, insufficient current setting, etc).

2) Something physically loose (motor coupling, leadscrew nut, etc.)

Don't know if this helps.

Tweakie.

6587

General Mach Discussion / Re: Lost Steps

« on: July 04, 2011, 03:33:30 AM »

Sorry to keep plaguing you with questions.

What I have observed is that when Z comes up to "zero" on the crossover it does not get to "zero" but rather comes up 3mm short.

Is that 3mm short on the Mach screen Z Axis DRO  or 3mm short in physical distance when the DRO correctly reads 0.0000 ?

Tweakie.

6588

General Mach Discussion / Re: Lost Steps

« on: July 04, 2011, 02:47:12 AM »

OK, At what point during the crossover move do you suspect that the 'extra steps or lost steps' are being generated ?
Perhaps if we know when they are occurring a solution may be easier to find.

Tweakie.

6589

General Mach Discussion / Re: Lost Steps

« on: July 04, 2011, 02:14:07 AM »

Stefan,

Returning to the surfboard - when you move from one side of the board to the other (with Z raised clear of the work) does the Z axis 'tick' steps during this crossover move ?

Tweakie.

6590

G-Code, CAD, and CAM discussions / Re: Autodesk 123D - Free 3D Design Software

« on: July 03, 2011, 11:56:42 AM »

Hi Sam,

Glad you are finding it interesting.
Others on the Phlatforum are exporting .stl or .dxf to convert to the GCode but they are sounding pretty pleased with their results.

Tweakie.